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11.
Three hundred and forty-two health professionals who deal with children, including general practitioners, paediatric residents and paediatric nurses were asked questions about their knowledge of infant feeding, particularly how they would recommend mothers to reconstitute milk formulae. A proportion of errors was noted in all groups, with errors occurring more frequently in the medical groups. Mothers seeking feeding advice are most likely to obtain the correct answers from paediatrically trained nurses.  相似文献   
12.
Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
13.
X-linked liver glycogenosis type II (XLG II) is a recently described X- linked liver glycogen storage disease, mainly characterized by enlarged liver and growth retardation. These clinical symptoms are very similar to those of XLG I. In contrast to XLG I patients, however, XLG II patients do not show an in vitro enzymatic deficiency of phosphorylase kinase (PHK). Recently, mutations were identified in the gene encoding the liver alpha subunit of PHK (PHKA2) in XLG I patients. We have now studied the PHKA2 gene of four unrelated XLG II patients and identified four different mutations in the open reading frame, including a deletion of three nucleotides, an insertion of six nucleotides and two missense mutations. These results indicate that XLG II is due to mutations in PHKA2. In contrast to XLG I, XLG II is caused by mutations that lead to minor structural abnormalities in the primary structure of the liver alpha subunit of PHK. These mutations are found in a conserved RXX(X)T motif, resembling known phosphorylation sites that might be involved in the regulation of PHK. These findings might explain why the in vitro PHK enzymatic activity is not deficient in XLG II, whereas it is in XLG I.   相似文献   
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In New Zealand white rabbits bearing the transplantable VX2 carcinoma intramuscularly in the hind limbs uniformly a granulocytosis syndrome developed, characterized by peripheral blood neutrophilia and marked granulocytic bone marrow hyperplasia, whereas the syndrome did not always develop in animals bearing the tumor intraabdominally. The relationship between the extent of pulmonary metastases and granulocytosis/bone marrow hyperplasia was significant (P less than 0.005). This positive correlation (correlation coefficient = 0.85) existed for both animals bearing intraabdominal tumors and animals bearing intramuscular tumors. The granulocytic syndrome occasionally occurred in rabbits with mild degrees of pulmonary metastatic involvement, but never with total absence of pulmonary metastases. Hypercalcemia occurred prior to the appearance of pulmonary metastases and was not essential to the development of granulocytosis. These data suggest that granulocytosis in VX2 carcinoma-bearing rabbits is dependent on the presence of tumor in the lungs and is not directly related to implantation site. This tumor-bearing animal model may be suitable for studies of tumor-associated granulocytosis in vivo.  相似文献   
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Oates J  Edwards C 《Histopathology》2000,36(4):341-347
AIMS: To evaluate HBME-1, WT1, calretinin and MOC-31 in the differential diagnosis of pleural mesothelioma and adenocarcinoma of the lung. METHODS AND RESULTS: Paraffin-embedded formalin-fixed blocks from six reactive pleuras, 42 mesotheliomas and 40 adenocarcinomas were used. Sections were stained for Leu-M1, HBME-1, calretinin, WT1 and MOC-31. Leu-M1 was positive or equivocal in 34% of mesotheliomas and in 78% of adenocarcinomas; reactive pleuras were all negative. HBME-1 was positive or equivocal in 76% of mesotheliomas and in 73% of adenocarcinomas; five reactive pleuras were positive. Calretinin was positive or equivocal in 92% of mesotheliomas and in 73% of adenocarcinomas; two reactive pleura were equivocal and four were positive. WT1 was positive or equivocal in 72% of mesotheliomas (excluding autopsy cases) and in 20% of adenocarcinomas; all reactive pleuras were positive. MOC-31 was positive or equivocal in 5% of mesotheliomas and in 90% of adenocarcinomas; all reactive pleuras were negative. The reaction with Leu-M1 was graded as equivocal in 25% of the adenocarcinomas. All 24 of the autopsy cases of mesothelioma were negative for WT1 and in many operative specimens only the periphery was stained. CONCLUSIONS: Neither calretinin nor HBME-1 are sufficiently discriminatory to be of use, even as members of a panel of antibodies. WT1 shows some promise, but it cannot be used on autopsy material. The utility of MOC-31 is confirmed, and outperforms Leu-M1.  相似文献   
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L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
20.
Hallam PJ, Mannucci P, Tripodi A, Bevan D, Laursen B, Tengborn L, Wacey A, Cooper DN. Three novel PROC gene lesions causing protein C deficiency. Clin Genet 1998: 54: 231–233. 0 Munksgaard, 1998
Missense mutations. three of them novel (Am210→Val, Asn248→ Ile, Ah355→Val), were found in the protein c ( PROC ) genes of 7 patients with inherited protein C deficiency associated with venous thrombosis. Comparison with the phenotypic effects of mutations in the analogous residues of factor IX causing hdernophilia B and the use of molecular modelling has provided explanations as to how these lesions might alter either the structure, function or secretion of the protein C molecules encoded.  相似文献   
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